Apnea of prematurity: from cause to treatment

Apnea of prematurity (AOP) is a common problem affecting premature infants, likely secondary to a “physiologic” immaturity of respiratory control that may be exacerbated by neonatal disease. These include altered ventilatory responses to hypoxia, hypercapnia, and altered sleep states, while the roles of gastroesophageal reflux and anemia remain controversial. Standard clinical management of the obstructive subtype of AOP includes prone positioning and continuous positive or nasal intermittent positive pressure ventilation to prevent pharyngeal collapse and alveolar atelectasis, while methylxanthine therapy is a mainstay of treatment of central apnea by stimulating the central nervous system and respiratory muscle function. Other therapies, including kangaroo care, red blood cell transfusions, and CO2 inhalation, require further study. The physiology and pathophysiology behind AOP are discussed, including the laryngeal chemoreflex and sensitivity to inhibitory neurotransmitters, as are the mechanisms by which different therapies may work and the potential long-term neurodevelopmental consequences of AOP and its treatment

Predictive Score for Identifying Survival and Recurrence Risk Profiles in Patients Undergoing Ventricular Tachycardia Ablation The I-VT Score

BACKGROUND: Several distinct risk factors for arrhythmia recurrence and mortality following ventricular tachycardia (VT) ablation have been described. The effect of concurrent risk factors has not been assessed so far; thus, it is not yet possible to estimate these risks for a patient with several comorbidities. The aim of the study was to identify specific risk groups for mortality and VT recurrence using the Survival Tree (ST) analysis method. METHODS: In 1251 patients 16 demographic, clinical and procedure-related variables were evaluated as potential prognostic factors using ST analysis using a recursive partitioning algorithm that searches for relationships among variables. Survival time and time to VT recurrence in groups derived from ST analysis were compared by a log-rank test. A random forest analysis was then run to extract a variable importance index and internally validate the ST models. RESULTS: Left ventricular ejection fraction, implantable cardioverter defibrillator/cardiac resynchronization device, previous ablation were, in hierarchical order, identified by ST analysis as best predictors of VT recurrence, while left ventricular ejection fraction, previous ablation, Electrical storm were identified as best predictors of mortality. Three groups with significantly different survival rates were identified. Among the high-risk group, 65.0% patients were survived and 52.1% patients were free from VT recurrence; within the medium- and low-risk groups, 84.0% and 97.2% patients survived, 72.4% and 88.4% were free from VT recurrence, respectively. CONCLUSIONS: Our study is the first to derive and validate a decisional model that provides estimates of VT recurrence and mortality with an effective classification tree. Preprocedure risk stratification could help optimize periprocedural and postprocedural care

Outcomes after repeat ablation of ventricular tachycardia in structural heart disease: An analysis from the International VT Ablation Center Collaborative Group

BACKGROUND: Data evaluating repeat radiofrequency ablation (>1RFA) of ventricular tachycardia (VT) are limited. OBJECTIVE: The purpose of this study was to determine the safety and outcomes of VT >1RFA in patients with structural heart disease. METHODS: Patients with structural heart disease undergoing VT RFA at 12 centers with data on prior RFA history were included. Characteristics and outcomes were compared between first-time (1RFA) and >1RFA patients. RESULTS: Of 1990 patients, 740 had >1RFA (mean 1.4 +/- 0.9, range 1-10). >1RFA vs 1RFA patients did not differ with regard to age (62 +/- 13 years vs 62 +/- 13 years), left ventricular ejection fraction (33% +/- 13% vs 34% +/- 13%), or sex (88% vs 87% men), but they more often were nonischemic (53% vs 41%), had implantable cardioverter-defibrillator shocks (70% vs 63%) or VT storm (38% vs 33%), and had been treated with amiodarone (55% vs 48%) or >/=2 antiarrhythmic drugs (22% vs 14%). >1RFA procedures were longer (300 +/- 122 minutes vs 266 +/- 110 minutes), involved more epicardial access (41% vs 21%), induced VTs (2.4 +/- 2.2 vs 1.9 +/- 1.6) and only unmappable VTs (15% vs 9%), and VT was more often inducible after RFA (42% vs 33%, all P 1RFA vs 1RFA (8% vs 5%, P 1RFA vs 1RFA (29% vs 24%, P 1RFA vs 1RFA if VT recurred (67% vs 78%, P = .003) but was equivalent if successful (93% vs 92%, P = .96). CONCLUSION: Patients requiring repeat VT ablation differ significantly from those undergoing first-time ablation. Despite more challenging ablation characteristics, VT-free survival after repeat ablations is encouraging. Mortality is comparable if VT does not recur after RFA at specialized centers

Ventricular Tachycardia Ablation in Severe Heart Failure An International Ventricular Tachycardia Ablation Center Collaboration Analysis

BACKGROUND: Ventricular tachycardia (VT) radiofrequency ablation has been associated with reduced VT recurrence and mortality, although it is typically not considered among New York Heart Association class IV (NYHA IV) heart failure patients. We compared characteristics and VT radiofrequency ablation outcomes of those with and without NYHA IV in the International VT Ablation Center Collaboration. METHODS AND RESULTS: NYHA II-IV patients undergoing VT radiofrequency ablation at 12 international centers were included. Clinical variables, VT recurrence, and mortality were analyzed by NYHA IV status using Kaplan-Meier analysis and Cox proportional hazard models. There were significant differences between NYHA IV (n=111) and NYHA II and III (n=1254) patients: NYHA IV had lower left ventricular ejection fraction; more had diabetes mellitus, kidney disease, cardiac resynchronization implantable cardioverter-defibrillator, and VT storm despite greater antiarrhythmic drug use (P<0.01). NYHA IV subjects required more hemodynamic support, were inducible for more and slower VTs, and were less likely to undergo final programmed stimulation. There was no significant difference in acute complications. In-hospital deaths, recurrent VT, and 1-year mortality were higher in the NYHA IV group, in the context of greater baseline comorbidities. Importantly, NYHA IV patients without recurrent VT had similar survival compared with NYHA II and III patients with recurrent VT (68% versus 73%). Early VT recurrence (</=30 days) was significantly associated with mortality, especially in NYHA IV patients. CONCLUSIONS: Despite greater baseline comorbidities, VT radiofrequency ablation can be safely performed among NYHA IV patients. Early VT recurrence is significantly associated with subsequent mortality regardless of NYHA status. Elimination of recurrent VT in NYHA IV patients may reduce mortality to a level comparable to NYHA II and III with arrhythmia recurrence

Successful ventricular tachycardia ablation in patients with electrical storm reduces recurrences and improves survival

Objective: The purpose of this study was to evaluate the characteristics and outcome of patients undergoing ablation after electrical storm (ES). Methods: Clinical and procedural characteristics, ventricular tachycardia (VT) recurrence, and mortality rates from 1940 patients undergoing VT ablation were compared between patients with and without ES. Results: The group of 677 patients with ES (34.9%) were older, were more frequently men, and had a lower ejection fraction, more advanced heart failure, and a higher prevalence of cardiovascular comorbidities as compared with those without ES (86.1% patients with ES had ≥2 comorbidities vs 71.4%; P <.001). Patients with ES had more inducible VTs (2.5 ± 1.8 vs 1.9 ± 1.9; P <.001), required longer procedures (296.1 ± 119.1 minutes vs 265.7 ± 110.3 minutes; P <.001), and had a higher in-hospital mortality (42 deaths [6.2%] vs 18 deaths [1.4%]; P <.001). At 1-year follow-up, patients with ES experienced a higher risk of VT recurrence and mortality (32.1% vs 22.6% and 20.1% vs 8.5%; long-rank, P <.001 for both). Among patients with ES, those without any inducible VT after ablation had a higher survival rate (86.3%) than did those with nonclinical VTs only (72.9%), those with clinical VTs inducible at programmed electrical stimulation (51.2%), and not-tested patients (65.0%) (long-rank, P <.001 for all). In multivariate analysis, ES remained an independent predictor of in-hospital mortality, VT recurrence, and 1-year mortality (P <.001). Conclusion: Patients with ES have a high risk of VT recurrence and mortality. Patient and procedure characteristics are consistent with advanced cardiac disease and longer and more complex procedures. In patients with ES, acute procedural success is associated with a significant reduction in VT recurrence and improved 1-year survival. © 2017 Heart Rhythm Societ

Sex and Catheter Ablation for Ventricular Tachycardia An International Ventricular Tachycardia Ablation Center Collaborative Group Study

Importance: Significant differences have been described between women and men regarding presentation, mechanism, and treatment outcome of certain arrhythmias. Previous studies of ventricular tachycardia (VT) ablation have not included sufficient women for meaningful comparison. Objective: To compare outcomes between women and men with structural heart disease undergoing VT ablation. Design, Setting, and Participants: Investigator-initiated, multicenter, observational study performed between 2002 and 2013, conducted by the International VT Ablation Center Collaborative Group, consisting of 12 high-volume ablation centers. Consecutive patients with structural heart disease undergoing VT ablation were studied. Structural heart disease was defined as left ventricular ejection fraction less than 55%, hypertrophic cardiomyopathy, or right ventricular cardiomyopathy, with scar confirmed during electroanatomic mapping. Exposures: Catheter ablation. Main Outcomes and Measures: Ventricular tachycardia-free survival and transplant-free survival were compared between women and men. Cox proportional hazard modeling was performed. Results: Of 2062 patients undergoing ablation, 266 (12.9%) were women. Mean (SD) age was 62.4 (13.3) years and 1095 (53.1%) had ischemic cardiomyopathy. Compared with men, women were younger, with higher left ventricular ejection fraction and less VT storm. Despite this, women had higher rates of 1-year VT recurrence following ablation (30.5% vs 25.3%; P = .03). This difference was only partially explained by higher prevalence of nonischemic cardiomyopathy among women and was actually most pronounced among those with ischemic cardiomyopathy. Conclusions and Relevance: In 12 high-volume ablation centers, women with structural heart disease have worse VT-free survival following ablation than men. Whether this is owing to differences in referral pattern, arrhythmia substrate, or undertreatment requires further study

Two-stage approach in the management of thoracic neuroenteric cyst with spinal extension: thoracoscopic excision following dorsal laminectomy

WOS: 000348446700003PubMed ID: 25236467Neuroenteric cysts (NC) are rare pathologies and localized generally in posterior mediastinum or abdomen where they may extend to spinal canal through a vertebral defect. Isolated spinal lesions require dorsal/ventral laminectomy and thoracic ones thoracotomy or thoracoscopy. Posterolateral approach via thoracotomy is generally performed for lesions with both thoracic and spinal components. Minimal invasive excision of a thoracic NC with spinal extension in an infant is presented herein. A term female newborn with an antenatal (26th week) diagnosis of congenital diaphragmatic hernia (CDH) was admitted. On physical examination, she was normal except mild dyspnea and CDH were excluded on radiogram. Left parenchymal opacity necessitated thorax tomography that revealed lobulated cystic lesion (6 x 3.5 x 4.5 cm) in posterior mediastinum. MRI showed intraspinal extension of the lesion through a hemivertebrae (6th). Two-stage procedure was planned for suspected neuroenteric cyst. First, intraspinal component was excised with dorsal laminectomy and the connection was closed. Then, the thoracic component was excised thoracoscopically. Histopathological evaluation confirmed the diagnosis. Total parenteral nutrition and high dose somatostatin analog was needed due to transient left chylothorax on postoperative course. She was well and symptom-free in postoperative period. Neuroenteric cysts may lead to misdiagnoses in antenatal period. MRI is critical to show spinal and vertebral pathologies in suspected cases. Thoracoscopy may safely be performed for thoracic lesions with spinal extension in two-stage approach following closure of the connection and excision of the spinal component